Battery substitute



Jan. 26, 1931. v, AMY 1,789,348

BATTERY= SUBSTITUTE Fi led June 29., 192'! INVENTOR E EST v AMY L ifld wORNEY Patented J an. 20; 193i ERNEST v. m on NEW Yomrn.'Y....AssIeNoR*To aAnrof ooRroItArIoNor, AMERICA, I fACORlPOR-ATION orDELAWARE 1 i BATTEBYQSUBSTITUTE' 'lpplicationzfil ed June-29,

The present invention relates to an A;

and B battery eliminator for radio apparatus and more particularly tomeans for providing a constant potential-to the ,filaments and plates ofvacuum tubes of a radio receiving set from a commercial directourrentsupply. V H I It is customary in the operationof radio receivingsets-to use astorage battery, com monly called the A battery, to supplythe filament current'and a' number of dry cells, commonly called the Bbattery tosupply the necessary plate potential; In order to obtainsatisfactory operation, it becomes necessary to keep the storage or Abattery continually charged and this requires a great deal of care andattention. On the other hand, the dry cells or B battery, while inoperation, undergo a constant decrease in terminal potential. When theyare first installed, they function manner, but their efliciency inoperation is almost directly proportional to the length of time thatthey are in operation. Their decrease in terminal potential and increasein internal resistance finally become so great that they must be removedfrom the circuit and new ones substituted.

In order to obviate the necessity of continually recharging the storagebattery and replacing the B battery, the present invention is concernedwith a circuit arrangement capable of changing the value and thecharacteristics of the potential from a 110 volt, commercial directcurrent supply, so that it may be used on the filaments and plates ofthe tubes in a radio receiver, without distortion or line. ripples.

My invention will best be understood by reference to the followingdescription taken in connection with the accompanying drawing in whichthe single figure shows a schematic wiring diagram of the circuitarrangement which is the subject of this disclosure.

Between the leads from 'thellO volt D. G. supply are connected a pair'ofcondensers G and C of two microfarads each. A choke coil L ofapproximately fifty henries is connected in the positive lead betweenthese cone in a first class 'densers.' The @011 L2 together with an.)densers G and or constitute a small-filterripple which is created "inrator at the powerv house;

5 and R in ser es are connected across the line, and; thenecessaryvoltages are tappedv on this resistance. In thefigure,-which is merelyillustrative of my invention, the 45V tap is taken'olfbetween' R and Rand-the 22V tap is taken off between R5 an e-" The detector platepotential taken from the 22V tap is controlled by-theQrl1eostat'R The90V tapnd the. B-tap are connected to the positive and negative leads,respectivelyr I For obtaining the filamentcurrenhia cUl T- rent choke Lisconnected to the positive lead of the line supply in front of choke Land connected in series with L are. resistances R5 and R the latterbeing connected to the negative lead of the line supply, from whichpoint the 6V negative tap is takeno flif From between the resistances Rand R a connection is made for the 6V positive lead, avariand relativefunction of the the above circuit arrangement invention M a It wasfoundby experience after numerous experiments with choke coils,condensers and resistances in variouscombinations and networks for A andB battery elimination that the above circuit was the only-one which gavesatisfactory operation i. e. no noticeable ripple in the receiver outputwhen operating from a power -supply socket which .which is I sufiicientforysuppressing .the.

thejD. G. gene- ,LResistances R ".55 V

filament -Lcurrent. The out s5 is the novel and important{feature-ofthis 7 had badinductive interference from sparking motorsorwhere line commutator ripples wereadmittedly bad, with the use of onlytwo choke coils for the complete eliminator. W lb was fou d t etthe mostseri us. noises from the average house lighting circuit introducedln areceiver operating from an A and B eliminator come from the A sup- "andpreceding the plate smoothing choke L This method'was'only foundto workon very quiet circuits where very little-ripple or induction noises werepresent.

My method is to shunt the D. C. power sup-1 ply with aninductance inserieswith a resistance. The function ofthe inductance is'to' offer ahigh reactance to the line disturbances and to keepthem from thefilament supply voltage to the receiver whichis obtained from the dropacross this series resistance shown Itwas io'undby experiment 'thatthisshunt c'hok'emeth'od of'smoothing the A? supply voltage was moreefiective' and required only halfthe number of choke coils required byany other known method and still obtain satisfactory operation under allline conditions; c l

The circuit arrangement as disclosed is positive in operationandsatisfactory'in all respects, the output voltages -ren'iainin'g con:stant-under all circumstances. v

Having thus described the nature of my invention, '1 claim r r 1. Acircuit arrangement adapted'to feed currents of constant potential tothe filaments' and anodes of thermionic tubes in ra dio receivers from adirect current'sourcei'neluding, a current carrying'choke coil and aresistancein series connected directly across the ter'minals of saidsource, a second choke coil connected directly to vthe po'sitiveterminal of said source, a pair of condensers connected from one side ofsaid source to the terminals of said last named choke to form with saidchoke an efiective filter, a resistance connected acr'oss'therterminals'of said filter, a'pl-urality' of anode potential terminals connected topoints on said resistance,a variable res'istance in one of saidconnectionsyand a pair of filament current terminalsoneof which isconnected to theineg'ative sideof said source and-the other of whichis"con= nected through a variable resistance to" a poi-nton said seriesresistance. 2. In-radio apparatus adapted to supply currents ofsubstantially constant potential to the filamentsand anodes of vacuumtubes in radio receivingsets from a direct current source, a currentcarrying choke and a'series resistance connected directly across saidsource, a filament current supply including a lead taken through avariable resistance from apoint on the series resistance anda secondlead ta'ken from a terminal of said source, ,a condenser inparallel'with said series choke and-resistance, a high impedance chokecoil having one end connected directly to one terminal of the source andtothe first named choke coil, a condenser connecting the other end ofsaid high impedance to the other terminal of said source, a resistanceparallel to said last narned-condenser-,,a plurality of terminalsconnectedto points onsaid resistance, and'a-variable resistance in oneof said connections w g a In a circuit arrange'ment for obtaining anodecurrent and filament current of constant potential from a direct currentsource, a high impedance choke coil connected directlytoIthepositiveterminal of said source for smoothing out the ripples in the platecurrent, a condensenconnecting one end of said choke mi-1 1:0the-negative end of said source, asecond choke coil having an inductanceof substantially henry and a resistance in series? there-with connecteddirectly mess the terlninals'of said source and a filament supplycomprising a pair of'leads" one take'n' fromapoint on"said' resistancethe other bein'g'taken from the negative side of saidisupply'y ERNEST vAMY

